Improvement in roofing-cements



UNITED STATES PATENT OFFICE.

G. W. GUSHING, OF CHICAGO, ILLINOIS.

IMPROVEMENT IN ROOFlNG-CEMENTS.

Specification forming part of Letters Patent No. 21,553, dated September 21, 1858.

To all whom it may concern.-

Be it known that I, GEORGE W. OUsHING, of the city of Chicago, in the county of Cook and State ofIllinois, have invented a new and Improved Roofing-Cement; and I do hereby declare that the following is a full, clear, and exact description of the component parts of and methods of compounding the same and applying it to use.

The component parts of the cement are asphaltum,coaltar, and thepitchy residue known as residuary gum, which is separated from the fatty substances in the manufacture of stearic acid for what are known as star candles, or for other purposes. I consider it desirable to vary the proportions of these ingredients in the two coats of the cement which are necessary to make a good roof. For the first coat I employ for every pint of coal-tar six (6) ounces of asphalt-um and two and onehalf (29;) ounces of the residuary gum; but for the second coat, to obtain more body, I employ for every pint of coal-tar eight (8) ounces of asphaltum and two and one-half(2-) ounces of residuary gum. These quantities serve for four (4) square feet of roof.

To make the cement, the asphaltum requires to be first pulverized, and then the several ingredients are placed together in a suitable pan or boiler over a moderate fire and boiled until the asphaltum and residuary gum are dissolved. The cement for the second coat will require to be boiled over a quick fire until about fifteen (15) minutes after the asphaltum and residuary gum have been dissolved.

Before applying the cement to the roof the roofboards are to be covered with a felt paper which has been saturated with coal-tar, and this paper is laid so that its edges lap each other, in the same manner as the edges of shingles, to the width of about four (4) inches, and if the walls of the building extend above the roof it is carried up them to the height of about six (6) inches. The paper having been laid as above described, the first coating of cement, while hot enough to keepitin afiuid state, is to be applied with a mop or brush. When the surface has been covered in this way a second covering of felt paper saturated with coal-tar is to be laid on in the same way as the first, but in such a manner as to break joints with the first. Laths are then to be nailed to the roof at intervals of about four feet apart and over the extreme edges of the paper, running in a direction transverse to the seams or joints in the paper; and then the second coating of cement is to be applied in the same manner as the first, and while it is freshz'. 6., before it is set-about one (1) or one and one-quarter (1%) pint of gravel or coarse sand is to be distributed over every square foot of surface.

The object of applying the cement between the two thicknesses of felt paper, as hereinbefore specified, is to preserve it from evaporation and preserve the first layer of paper and protect it from injury.

What I claim as my invention, and desire to secure by Letters Patent, is

The roofing-cement composed of asphaltum, coal-tar, and the residuary gum herein specified,combined in about the proportions herein stated.

GEORGE W. OUSHINP Witnesses:

JOHN CLARK WANDS, Amos J. VANDENBERGH. 

